1. Field of the Invention
The present invention relates to a cart for transport of tools, supplies, equipment, and other material over a curved surface in connection with work on that surface.
2. Description of the Related Art
There are buildings and other types of structures which have a curved roof or upper surface which changes in shape over its downward extent or slope, often as well across its lateral extent or span. An example with which applicant is familiar is the generally dome-shaped roof of a reactor containment building at an electrical power generating facility. Upper portions of this curved roof or surface are often on the order of two hundred feet or so, or even more, above the earth's surface in the nearby area.
From time to time, repairs, maintenance or inspections must be made on the surface of this type of curved roof surface. This required equipment and tools for the service crew. The service crewmembers had need for several types of equipment and tools while working on the roof, and the equipment not in use had to be safely stored. Clearly a loose object falling several hundred feet from the roof was a major safety hazard.
However, the tools and equipment had to be kept available on the roof by the service crew as needs arose to use them. Further, the service crewmembers needed their hands and arms free for work purposes. Each service crewmember for safety reasons wore a safety harness attached by a cable or rope to a connection at the top of the roof.
There were competing demands on service crews to be able to safely work easily and quickly on these elevated, irregular-shaped work surfaces and yet have tools and equipment readily at hand. One possible approach was to have additional work crewmembers assigned to provide and hold the tools and equipment. This solution increased the number of workers in a relatively risky locale and could give rise to safety concerns.
So far as is known, carts for general transport of items over flat or planar surfaces did not lend themselves to use on curved surfaces of roofs and the like. Stability of the cart on the curved surface was one concern, while ease of movement of these types of general transport carts over the curved surface was another. Carts adapted for transport or storage of special items of equipment or cargo on flat or planar surfaces suffered from the same concerns.